Opamp power supply starting out bad and then making it better 

Multiplier supply is fine if you have a single winding transformer but need split rail supply for lower currents. Plop capacitance multipliers at the outputs and you have a solid hi fi preamp supply there.

good demonstration, I couldnt hear a darn difference!

Early in my career (1970) i worked for Analog Devices as a engineering technician so I got a good grounding in opamps. Even early opamps have a pretty good PSRR (power supply rejection ratio) and that makes them somewhat forgiving with regard to ripple. That said a good clean supply is important if you want the best performance

I was waiting for the full bridge rectifier myself.

Thanks for posting.

if the 10 ohm resistors are 1W resistors, the output will max out those resistors at 80mA, which will create thermal issues. 50mA is a more likely rating for its output.

Good demonstration, definitely increased my understanding, thanks! Also a nice project to copy and experiment with. Time for a parts rummage...

Another great video! Can you teach us to build a switching power supply? Maybe a dual rail thing?

That was really good, John. I'm pretty sure we would have heard a big difference if you used super expensive cables.... ! Heh.

Always a great video! Thank you - I look forward to your next video;)

you rock man great work

Great topic

Hello John, Good to see you and a very informative, as always video. Glad you are doing well and I hope your Brother is too. Last week, starting on the 13th, I had 12 little heart attacks and a Stent put in. Doing good, still doing my chores, a bit slower. It was my 1st Diagonal apparently, that had a blockage. 48 hours from getting admitted, to being released, I don't stay down to long, I've got JAT videos to watch. All the best from Oregon, C.

The professional use line level circuits operate on signals that can significantly exceed 2V. There must be enough headroom. Even newer opamp designs can work better with a reasonably high supply voltage(better linearity for signals close to rails, sometimes better slew rate,...). Sometimes it is necessary to use chips with j-FET inputs and common-mode input voltage range turns out to be a limitation.

For a low current circuit like this were absolute voltage stability is not really an issue you could use a capacitance multiplier to pretty much eliminate the ripple.

Awesome video 👍 I'd love to see one experimenting on power amplifier supplies

Point taken. Now, let's make video on high performance, audiophile grade op amp power supply. Cheers!

Hi, Jhon! I've been playing with op amps recently (Frecuency response, output voltage, current supply, negative feedback, ground, bandwidth, slew, etc). I saw that some don't sound too well, some high performance ones sound better but there is a "point" when they are not too different between them. I'd like to ask, how to choose a good op amp for audio aplications? Maybe if you find this subject interesting, make a video in the future where we can see the difference between a non suitable one, a good one and when is an overkill. Thank you!

Would have been interesting to see the regulators performance with less pre-filtering. How little can you get away with?

Please make a variable dual rail power supply circuit for powering any circuit including audio amplifiers

It would be interesting to see the half wave supply compared with a full bridge rectified with a resistor divider virtual ground supply.

Great video, but because of what opamps do, EEVblog also explained it well saying that opamps try to equalize negative and positive inputs. I wasn't too surprised by this. However, I recently realized that transistors themselves also don't care much about their power input, because they are a current device. They just amplify the current coming in through the base, right? Depending on temperature and operating range. So power amplifiers, mostly, should also inherently not care much about some level of noise on the power input. Unless mistakes were made. Do I understand that correctly?

I hear more dynamic range and betetr high frequency response in the first sample , let`s see which is which

Nice 👌 great information 👍

If you use simple transistor regulator say zener diode and high gain single power transistor in pair to compare them with voltage regulator IC in next video it would be a perfect comparison.

Wouldn't a full bridge reduce the capacitor requirements?

Am I missing something, but wouldn't you want a LC-pi-filter rather than an RC-pi-filter? Of course you would then need a series RC-network to prevent the filter from ocillating, but you should get a better result with that. Annotation: Expenation why this is a bad idea are in the comments.

I have questions - 1. What should be the output capacitor value for the regulator IC if the required load current is 500 mA - 1 Amp (higher current version regulator IC) for running low power audio amplifier chips like Lm386, Tea2025 etc ? 2. Is it sufficient to have only one electrolytic capacitor at regulator output or a combination of ceramic capacitor (0.1 uF or so) for suppressing high frequency noises ?

Surprised you didn't use a capacitance multiplier. Dual of course.

What about virtual battery operation like that used in the TECHNICS SUA-900 MKII

SVR? I thought it was called PSRR on the datasheets?

You could do another test with a capacitance multiplier. Trying it before or after the regulator. I've always wondered if such a circuit works well and if work better before or after the 78xx/79xx

100uF vs battery 08:51 1st sample 09:37 2nd sample My comment : at my 90% headphone volume from mobile, I just cant hear the difference, not even the noise. Are you serious john? ;)

I have seen power amplifier transfomer center tap connected with pre amp ground and connected to metal body of amplifier. Somebody said connection with body of amplifier is mandatory to reduce noise. Is it? If so how it will reduce noise?